In electronic circuits, the processing units are usually supplied by a power supply voltage at the terminals of a capacitor.
However, there is a critical voltage threshold below which the processing unit will no longer be able to operate correctly. For example, it is possible that in case of failure of the power supply the processing unit is only supplied by the capacitor which discharges more or less quickly according to the consumption of the processing unit, and therefore the voltage drops below the threshold.
It is therefore advisable to switch off or reinitialize the processing unit before this threshold is reached, in order, for example, to avoid a loss of information or damage to the processing unit.
There are solutions for monitoring the power supply voltage of a processing unit, and for switching off or reinitializing the processing unit on detecting a threshold voltage. However, these solutions have a significant current consumption, which may be problematic in applications that require both monitoring the power supply voltage and low current consumption.